Over 1.1 million conceptuses and fetuses die spontaneously each year, nearly 28,000 after 20 weeks'gestation. 12.5% of all infants are delivered prematurely, and the cost of care for the prematurely born is nearly 27 billion dollars annually. Prenatal assessment is currently dominated by ultrasound-based techniques;however, these are limited in their ability to evaluate cardiac arrhythmia, conduction, ischemia, and heart rate variability. Recently, we and other researchers have shown that a relatively new technique, fetal magnetocardiography (fMCG), holds great promise to provide specific diagnostic and electrophysiologic data to better manage pregnancies in which the fetus suffers from cardiac disease, arrhythmia, is undergoing interventional procedures, or is at high risk for intrauterine demise. It can provide further antenatal reassurance, lowering unnecessary pre-term delivery of high risk pregnancies. Currently in the Midwest, women are traveling over 100 miles for this procedure when their doctor has identified an arrhythmia or high- risk condition. Nearly 200 fetal arrhythmia pregnancies have been studied to date at the University of Wisconsin, the only dedicated fMCG center in the United States. This represents a small fraction of those pregnancies for which ready access to fMCG could have positively impacted patient care. The goal of this research program is to construct and operate a prototype mobile imaging system to promote the development and adoption of fMCG. The project is unusually challenging and extensive in scope;however, we believe that our consortium of commercial and university partners has the necessary experience and expertise to implement this ambitious concept. In the Phase I study, we will conduct a magnetic site survey, fabricate and test prototype shields, and analyze various sensor configurations in order to optimize the performance of the equipment and to establish the technical feasibility of obtaining high-quality fMCG recordings in a mobile system. The goal of the Phase II project is to construct a prototype mobile fMCG system that will travel between hospitals in a 4-state region, making this technology available to a much greater patient population. PUBLIC HEALTH RELEVANCE The proposed research will advance prenatal health care by promoting the development and adoption of fetal magnetocardiography (fMCG), a promising new technology for fetal evaluation. This will be accomplished by constructing a mobile fMCG system that will travel between hospitals in a 4-state region. This technology has proven to be extremely valuable in the management of fetuses with cardiac complications and has the potential to shed light the causes of unexplained sudden fetal death.